3-acyloxy-9,11-oxido-5,7-pregnadien-20-one-21-acetate adducts



Patented Dec. 9, 1952 S-ACYLOXY- 9,11- OXIDO 5,7 -PRE GNADIEN- ZO-QNE-Zl-ACETATE ADDUCTS Robert H. Levin, A Vern McIntosh, Jr., and George B. Spero, Kalamazoo, Mich., assignors to The Upjohn Company, Kalamazoo, Mich., a

corporation of Michigan No Drawing. Application August 23, 1950, Serial N0. 181,112

7 Claims. 1 The present invention relates to adducts of 3- acyloxy 9,11 oxido-5,7-pregnadien-20-one-2lacetates with certain dienophilic acids, anhydrides, and esters, and to a process for the production thereof.

The compounds of the present invention may be represented by the structural formula:

wherein Ac is the residue of an organic carboxylic acid, especially such acids containing from one to eight carbon atoms, inclusive; and A is an adduct radical derived from a dienophile selected from the group consisting of maleic acid, maleic anhydride, and maleic acid diesters containing from one to eight carbon atoms, inclusive, in the esterifying group.

It is an object of the present invention to provide a novel group of compounds which are useful in the preparation of steroid compounds containing an oxygen atom at carbon atom eleven. Another object of the invention is the provision of a process for the production of the novel compounds, adducts of 3acy1oxy-9,1l-oxido-5,7- pregnadien-ZO-one2l-acetates. Other objects of the invention will become apparent hereinafter.

The compounds of the present invention, as previously stated, are useful in the preparation of steroid compounds having an oxygen atom attached to carbon atom eleven. Such compounds are of particular interest in the field of steroid research due to the biological activity of the cortical hormones and certain known derivatives thereof, which oxygenated steroids are known to have biological effects diifering markedly from the unoxygenated steroids. It is, therefore, of importance to investigate the oxygenated derivatives of such adducts, particularly those oxygenated at carbon atom eleven, as well as their transformation products. The importance of such investigation is moreover emphasized by the acute shortage of adrenal cortical hormones, and the absence of any present suggestion for alleviation of the said shortage except through organic synthesis.

Novel compounds of the present invention which are of particular interest are those compounds of the above generic formula wherein Ac represents the residue of a carboxylic acid containing up to and including eight carbon atoms. Among the acids which can be used are formic, acetic, propionic, butyric, valeric, hexanoic, heptanoic, octanoic, succinic, glutaric, cyclopentanoic, benzoic, toluic, and the like. Preferred acids are the lower-aliphatic acids. The acids may also contain substituents, such as halo, alkyl, and methoxy, which are non-reactive under the reaction conditions employed. The adduct bridge (--A) in such compounds may be represented by the graphic formula:

(ii-000R H wherein R represents hydrogen or the organic residue of an alcohol. Such esters include the methyl, ethyl, propyl, isopropyl, butyl, isobutyl, lauryl, heptyl, octyl, cyclohexyl, cyclopentyl, benzyl, and the like esters. The esterifying radical may also contain non-reactive substituents, such as halo, methoxy, or hydroxy, if desired. While the esters of the maleic acid adduct are described herein with particular reference to the methyl esters, the preferred embodiment of R is a loweralkyl radical containing from one to eight carbon atoms, inclusive. Alternatively, the adcluct may be depicted by the graphic formula:

which is representative of the maleic anhydride adduct.

The compounds of the invention are usually colorless crystalline solids, whichare soluble in ether, halogenated hydrocarbons, acetone, ethyl acetate, and benzene. The anhydride adducts are readily converted into diester adducts by esterification with conventional reagents such as the diazoalkanes [Wilds et al., J. Org. Chem. 13, 763 (1948) 1. Conversely, the anhydrides may be hydrolyzed to the dibasic acids which in turn may be converted into their corresponding anhydrides either by heat alone or preferably with a mild dehydrating agent such as acetic anhydride and the like, or into the diester adducts in the same manner as the anhydride.

The compounds of the present invention have the formula:

AcO-

wherein A and Ac have the values stated previously.

The preparation of these 3acyloxy-9,1l-oxide- 5,7-pregnadien--one-2l-acetate adducts involves the oxidation of the corresponding 3- acy1oxy-5,'I,9(11) -pregnatrien-20-one 21 acetate adduct using an organic peracid or concentrated hydrogen peroxide as the oxidant. Hydrogen peroxide is usually employed in the form of a twenty to ninety percent by weight aqueous solution, a thirty percent solution being preferred. The reaction is carried out by stirring the adduct and oxidant together, preferably in an organic medium which is non-reactive under the reaction conditions. Suitable media include chloroform, carbon tetrachloride, mixtures of ether and chloroform, glacial acetic acid, and many others. The ratio of oxygenfurnishing agent to steroid can be varied considerably within broad ranges. Ratios of up to twenty moles to one are operative, but ratios of from one to four moles per mole of steroid are perferred for attainment of optimum yields, the exact ratio being preferably varied inversely with the reaction time desired to be employed. The temperature of the mixture is usually maintained at from about zero degrees to about 100 degrees Centigrade for a suitable period, e. g., from about one-half to twenty-four hours, depending on the concentration of oxygen-furnishing agent, and the 9,11-oxido compound then isolated in any convenient manner, such as by volatilizing the reaction medium, extracting the residue with chloroform, filtering, volatilizing the chloroform, and recrystallizing the residue, e. g., from eighty percent aqueous acetone. Alternatively, the compounds may be recovered by pouring the reaction product into water, filtering the solution, and drying the precipitate. The 9,11-oxido compound is usually obtained in a state of high purity after one or two recrystallizations. A convenient reaction medium when the oxidant is hydrogen peroxide is glacial acetic acid, and, when such is employed, the 9,11- oxido compound is separated readily by pouring the reaction product onto cracked ice to precipitate the 9,11-oxido compound, filtering, and rccrystallizing the dried crude product, e. g., from ethyl acetate.

The starting 3-acyloxy-5,7,9(11) -pregnatrien- 20-one-2l-acetate adducts have the formula:

CH3 CHr-O CCll".

on, =0 H G wherein A and Ac have the values given in the foregoing. The 21-acetoxy compounds are conveniently prepared by reaction of the selected 3-acyloxy-5,7,9 11) -pregnatrien-20-one maleic acid, maleic anhydride, or maleic acid diester adduct with lead tetraacetate. The lead tetraacetate is ordinarily employed in an amount in excess of the theoretical, and an organic solvent for the reaction is employed, for example, acetic acid and water, benzene, or ether, with acetic acid being preferred. The reaction may conveniently be carried out at a temperature between about twenty and degrees centigrade. with temperatures of about 50-60 degrees centigrade, which are readily obtainable by employment of a water-bath, being preferred. The lead tetraacetate usually goes into solution quite readily, and the reaction is complete in from 24 to 96 hours. The 21-acetoxy adduct may then be recovered by evaporating the solution under a vacuum, dissolving the residue in ether, washing with water, drying, and recrystallizing from a solvent, such as alcohol, if desired, or in other conventional manner.

The 3-acyloxy-5,7,9(1l) -pregnatrien 20 one adducts are conveniently prepared by the selective oxidation of an enol ester of an adduct of 3-acyloxybisnor-5,7,9(l1) cholatrien 22 al, represented by the formula:

ACO-

r CHCHO 3 wherein A and Ac have the values previously given, to the action of an acid anhydride or an acid halide in the presence of an alkaline salt of the acid. The starting 3-acyloxybisnor-5,7,9- (11)-cholatrien-22-al adducts can be prepared from adducts of 3-esters of dehydroergosterol by selective oxidation as described and claimed in the copending application Serial No. 111,100 of Robert H. Levin, filed August 18, 1949, and as more fully described hereinafter.

The 3-esters of dehydroergosterol, from which the 3-acyloxybisnor-5,7,9(11)cholatrien-22-al adducts are prepared, can be synthesized in several Ways starting with ergosterol. For example, ergosterol can be transformed to dehydroergosterol with mercuric acetate according to known methods [Windaus et al., Ann. 465, 157 (1928)] and the 3-hydroxy group of the dehydroergosterol acylated by known procedure. Alternatively the 3-hydroxy group of ergosterol can be acylated prior to the preparation of the dehydro derivative a procedure which is particularly preferred in the preparation of the 3-acetoxy derivative. The adducts of dehydroergosterol are then prepared by the addition of maleic anhydride or the like to dehydroergosterol or a 3-ester thereof according to known methods [Honigmann, Ann. 508, 89 (1934)]. The anhydrides can then be converted to their corresponding acids and esters if desired.

The ester group, when present in the 3-position of dehydroergosterol, is for the purpose of protecting the 3-hydroxy group in subsequent chemical reactions. For this purpose any convenient ester of an organic carboxylic acid, which is non-reactive under the conditions of the reaction, is suitable. The preferred acids are the fatty acids such as formic, acetic, propionic, butyric, valeric, hexanoic, heptanoic, octanoic; dibasic acids such as malonic, succinic, phthalic; cycloaliphatic acids such as oyclopentanoic and cyclohexanoic; and aromatic acids such as benzoic, toluic, and the like. The acids may also contain substituents such as halogen, alkyl, the methoxy radical, and the like, and these substituents will be carried throughout the synthesis. If desired, the acyl group can be changed to another acyl group by saponifying the ester to give a 3-hydroxy compound, which can then be re-esterified as previously described.

A preferred method for preparing some of the dehydroergosteryl adducts comprises the saponification of a 3-acyloxy-adduct of dehydroergosterol with dilute alkali followed by acidification. The B-hydroxy dicarboxylic acid thus formed can be converted to the S-hydroxy anhydride by heat, or it can be converted to any desired 3-acyloxy anhydride adduct by heating under reflux with the appropriate acid anhydride or chloride in pyridine solution. Dialkyl esters of the previously mentioned dicarboxylic acid adducts can be prepared by subjecting the acid to the action of an esterification reagent such as diazoalkane [Wilds et al., J. Org. Chem. 13, 763 (1948)], e. g., diazomethane, diazoethane, diazobutane, and the like.

The selective oxidation of an adduct of dehydroergosterol, or a 3-ester thereof, to produce an adduct of 3-hydroXybisnor-5,7,9(11) cholatrien- 22-al, or a 3-ester thereof, is accomplished by dissolving the dehydroergosteryl adduct in a suitable solvent, cooling to about minus 80 to plus 30 degrees centigrade, and passing ozone into the solution until about 1.0 to 1.25 moles of ozone per mole of adduct have been absorbed. The temperature of the solution should be maintained below plus 30 degrees centigrade, preferably between a temperature of minus 30 and minus 70 degrees centigrade, during the addition of ozone, although temperatures as low as minus and as high as plus 30 degrees centigrade are operative. The lower temperatures of the preferred range are readily obtained by cooling the solution of the adduct with a bath of solid carbon dioxide in acetone or the like, although various other methods of cooling can be used. Many of the customary solvents used in ozonizations such as chloroform, acetic acid, carbon tetrachloride, ethylene chloride, methylene chloride, and the like, can be used.

The ozonides are then decomposed under reducing conditions, that is, in the absence of oxidizing agents, whether added or formed in the course of the reaction by products of decomposition of the ozonide. This means that excess oxygen formed by decomposition of the ozonide is prevented from formin hydrogen peroxide by combining with any moisture present, and that molecular oxygen is prevented from oxidizing the aldehyde thus formed. This can be conveniently accomplished by decomposing the ozonide in glacial acetic acid by the addition of finely-powdered zinc.

As is conventional with ozonizations when conducted in solvents, other than glacial acetic acid, the solvent used for ozonization is replaced, after completion of the ozonization, by adding glacial acetic acid and removing the lower-boiling solvent by fractional distillation. Alternatively, the solvent can be removed by careful warming under reduced pressure prior to the addition of glacial acetic acid, if desired.

After decomposition of the ozonide and removal of the zinc, the aldehyde can be recovered by diluting the acetic acid with water, or in other conventional manner, such as by formation of an aldehyde derivative, e. g., the dinitrophenylhydrazone.

Adducts of 3,22-diacyloxybisnor-5,7,9(11),20- (22) cholatetraenes [22-eno1-esters of 3-acyloxybisnor-5,7,9(11)cholatrien-ZZ-al adducts] can be conveniently prepared by heating the corresponding B-hydroxy or acyloxy aldehyde maleic acid, maleic acid anhydride, or maleic acid ester adduct with a large excess of an organic carboxylic acid anhydride in the presence of a small amount of the alkali metal salt of the acid corresponding to the anhydride employed or an acid catalyst such as para-toluene sulfonic or sulfuric acid. The preferred anhydride is acetic anhydride, but other anhydrides, such as propionic, butyric, valeric, hexanoic, and octanoic anhydrides, as well as benzoic acid anhydride, ortho-toluic acid anhydride, and the like, are also operative. The acid anhydrides can also be substituted by non-reactive groups, such as halo, alkyl, and methoxy, as in the case of chloroacetic, ortho-toluic, or methoxybenzoic acid anhydrides. The reaction can be conveniently followed by 0bserving the color changes in the reaction mixture,

optimum yields being obtained by discontinuing the application of heat when the col-or of the solution changes from yellow to brown. Ordinarily the reaction is heated at about degrees centigrade for from about four to six hours, but temperatures as low as 100 and as high as degrees centigrade are also operative. The reaction is usually conducted at the boiling point of the anhydride, but in the case of the higherboiling anhydrides, such as benzoic anhydride, a suitable temperature control, such as 100-150 degrees centigrade, must be used, since the adduct otherwise tends to decompose in the higher temperature range. If a B-hydroxy aldehyde adduct is thus reacted with an anhydride, the hydroxy group will be acylated, and, similarly, if a maleic acid adduct is used instead of a diester or an anhydride, the anhydride will be formed. The enol ester can be isolated by removing the excess anhydride under reduced pressure and separating the enol ester from alkali metal salts, which procedure yields a product sufiiciently pure for most purposes, but which can be further purified by recrystallization from acetone-water, acetonepentane, or like solvents, if desired.

The ozonization of the thus-prepared enol acylate involves dissolving the enol ester in a suitable solvent, cooling to about minus eighty degrees Centigrade to plus thirty degrees centigrade, and passing ozone, ozonized air, 01' ozonized oxygen into the solution until about 1.0 to about 1.25 moles, preferably 1.0 to 1.1 moles, of ozone per mole of adduct have been absorbed. The addition of ozone to the 20:22 double bond is so rapid that only a small amount of ozone escapes from the reaction mixture, and the amount of ozone ordinarily required therefore closely approximates the theoretical amount. Loss to the solvent, if any loss occurs, must be taken into consideration in calculating the amount of ozone to be introduced. The temperature of the solution should be maintained below plus thirty degrees centigrade, preferably between a temperature of minus thirty and minus seventy degrees centigrade, during the addition of ozone, although temperatures as low as minus eighty and as high as plus thirty degrees centigrade are operative. The lower temperatures of the range are readily obtained by cooling the solution of the adduct with a bath of solid carbon dioxide in acetone or the like, although various other methods of cooling may be employed. Many of the customary solvents used in ozonizations, such as chloroform, methylene chloride, ethylene chloride, carbon tetrachloride, acetic acid, and the like, can be used for the ozonization reaction.

The 20:22 ozonides thus produced are then decomposed under conditions normally employed for decomposition of such compounds. This can conveniently be accomplished by decomposing the ozonide with hydrogen peroxide, by hyrolysis, with zinc in glacial acetic acid, or by a catalytic amount of colloidal metal such as silver, platinum, or palladium in a solvent, such as glacial acetic acid, alcohol, or ethyl acetate, in which latter case reductive conditions, e. g., a hydrogen atmosphere, are also employed. The use of reductive conditions is well established in the art [Hill and Kelly, Organic Chemistry, page 53, The Blackiston Company, Philadelphia (1934); Church et al., J. Am. Chem. Soc. 56, 176484 (1934) Gilman, Organic Chemistry, Second Edition, page 636, John Wiley and Sons, New York (1943); Long, Chem. Reviews 27, 452-454 (1940)].

As is conventional with decomposition of ozonides with zinc, when the ozonizations are conducted in solvents other than glacial acetic acid, the solvent used for the ozonization is replaced, after completion of the ozonization, by adding glacial acetic acid and removing the lower-boiling solvent by fractional distillation, or the solvent can be removed by careful warming under reduced pressure prior to the addition of acetic acid, if desired. After decomposition of the 20:22 ozonide and removal of the metal, the ketone can be recovered by diluting the acetic acid with water, or by other conventional procedure for the recovery of ketones, such as by formation of a carbonyl derivative, e. g., the 2,4-dinitrophenylhydrazone. Recrystallization from acetone or the like results in a more highly purified ketone product. The 3-hydroxy ketones are prepared by saponification of the 3-acyloxy group, to give the 3-hydroxy ketone diacid, which can be converted to the anhydride or a diester, if desired. The 3-acyloxy diacids are prepared by the careful reaction of the 3-acyloxy anhydrides With two molecular equivalents of alkali.

The following examples are illustrative of the process and products of the present invention, but are not to be construed as limiting.

PREPARATION 1.DIMETHYL Mariana -inpucr or DEHYDROERGOSTERYL Brxzoa'rn To a solution of 21 grams of dimethyl maleate adduct of dehydroergosterol in 69 milliliters of warm pyridine was added 9.5 milliliters of benzoyl chloride. After standing at room temperature for fifteen minutes, the mixture was poured into 1400 milliliters of ice-water and the solid removed by filtration, dried, and recrystallized from acetone. There was thus obtained 26.4 grams of dimethyl maleate adduct of dehydroergosteryl benzoate, melting at 203 to 205.5 degrees centigrade.

PREPARATION 2.DIMETHYL Blaming Annuc'r or Dnnroaonacosrrurr. ACETATE In a manner essentially that described in Preparation 1, the dimethyl maleate adduct of dehydroergosteryl acetate, melting at 177 to 179 degrees centigrade, was prepared from the dimethyl maleate adduct of dehydroergosterol and acetyl chloride.

PREPARATION 3.DI.\1ETHrL HALEATI; Apmrcr 01- DEHrDxoIsI:cos'riznrr. Fonzuxru A solution of six grams of dimethyl maleate adduct of dehydroergosterol in fifty milliliters of 87 percent formic acid was heated under reflux for one hour, cooled, and the dimethyl maleate adduct of dehydroergosteryl formate filtered therefrom. Upon crystallization from acetone, the purified material melted at 177.5 to 178.5 degrees centigrade.

PREPARATION 4.-)L\L1 ;Io A on) Apnoea DlCIIYDROIEIIGOSTEROL A solution of 2.0 grams of sodium hydroxide in twenty milliliters of water was added to a solution of 1.73 grams of the maleic anhydride adduct of dehydroergosteryl acetate (M. P. 230-232 degrees centigrade) in forty milliliters of dioxane. The mixture solidified, but dissolved on addition of 300 milliliters of water and heating to eighty degrees centigrade. After half an hour the solution was cooled and made acid With aqueous three normal hydrochloric acid, to give 1.61 grams of precipitate. On crystallization from a dioxane-water mixture, the maleic acid adduct of dehydroergosterol melted at 190-192 degrees centigrade.

The maleic acid adduct of dehydroergosterol from Preparation 4 was dissolved in a mixture of seven milliliters of warm pyridine and fourteen milliliters of heptylic anhydride, and the mixture heated under reflux for one hour. About eighty percent of the reaction solvent was re- 9 i moved under reduced pressure, and the residue thendissolved in methyl alcohol. The methyl alcohol solution was concentrated and cooled to yield 4.8 grams of the maleic anhydride adduct of 3-heptanoyloxydehydroergosterol, melting at 186-1915 degrees centigrade.

PREPARATION 6.\iALEIc ANHYDRIDE ADDUGT OF 3- BETAACETOXYBISNOR-5,7,9 (11) -oHoLArRIEN-22-AL A solution of 5.35 grams of the maleic anhydride adduct of 3-beta-acetoxydehydroergosterol in 107 milliliters of methylene chloride was cooled to about minus seventy degrees centigrade and ozonized until 505 milligrams of ozone had been absorbed. The temperature of the solution was then raised to about plus ten to fifteen degrees centigrade, whereupon seventy milliliters of glacial acetic acid was added and the methylene chloride removed under reduced pressure. Seven grams of zinc dust was then added to the cold solution at a uniform rate over a period of ten minutes, while keeping the reaction temperature below plus twenty degrees centigrade. After being stirred for fifteen minutes, the mixture was filtered and the filtrate poured into water. There was thus obtained 4.31 grams of maleic anhydride adduct of 3 beta acetoxybisnor- 5,7,9(11)-cholatrien-22-al, a fine white powder which melted at 187-197 degrees centigrade.

To a solution of 0.30 gram of the maleic anhydride adduct of 3-beta-acetoxybisnor-5,7,9(11)- cholatrien-ZZ-al, to thirty milliliters of ethanol, was added twenty milliliters of alcohol containing one percent 2,4-dinitrophenylhydrazine and three percent concentrated hydrochloric acid. The mixture was allow to stand for one hour at room temperature and then placed in a refrigerator to complete precipitation of the yellow crystals. The precipitate was then collected and recrystallized from a mixture of chloroform and alcohol, to give the 2,4-dinitrophenylhydrazone of the maleic anhydride adduct of 3-beta-acetoxybisnor-5,7,9 (11) -cholatrien-22-al, melting at 269-271 degrees centigrade.

PREPARATION T.N[ALEIC ANHYDRIDE ADDUCT F 3- BETA-ACETOXYBISNOR-5,7,9 (11) -CHOLATRIEN-22-AL A two-liter, round-bottom flask was charged with fifty grams (0.93 mole) of dehydroergosteryl acetate maleic anhydride adduct and one liter of methylene chloride. The solution was cooled to Dry-Ice temperature with a trichloroethylene bath and ozonized oxygen passed through at a rate of 1200 milliliters of oxygen per minute (at this rate the ozonizer was producing about 36 milligrams of ozone per minute). The flow of ozonized oxygen was maintained for 128 minutes, a total of 4608 milligrams (105 percent) of ozone being passed into the solution. The reaction mixture was transferred to a two-liter, round-bottom flask fitted with a capillary and a condenser for downward distillation, 300 milliliters of acetic acid added, and the methylene chloride distilled over in vacuo at forty degrees centigrade or below. The flask was then placed in a water bath and fitted with a stirrer. An additional 200 milliliters of acetic acid was added and the ozonide decomposed by the addition of fifty grams of zinc dust. The zinc dust was added in portions over a period of twenty to thirty minutes while the solution was stirred and the temprature maintained at seventeen to twenty degrees centigrade. After addition, the mixture was stirred for another twenty minutes and then filtered. The precipitated zinc dust was washed by filtering 100 milliliters of acetic acid therethrough, and the filtrate gradually diluted with water (1100 to 1200 milliliters) until the product had been drowned out. The product was then cooled in the refrigerator overnight and filtered. The yield of crystalline product was 42 grams, assaying 89-95 percent of the desired aldehyde.

PREPARATION 8 In a manner essentially that described in Preparation 6, the following compounds were prepared.

(1) Maleic anhydride adduct of S-beta-formoxybisnor-5,7,9(11) -cholatrien-22-al, melting at -130 degrees centigrade. 2,4-dinitrophenylhydrazone, melting at -168 degrees centigrade.

(2) Maleic anhydride adduct of 3-beta-heptanoyloxybisnor-5,7,9 (11) -cholatrien-22-al, melting at 1975-19!) degrees centigrade. 2,4-dinitrophenylhydrazone, melting at 253-257 degrees centigrade.

(3) Dimethyl maleate adduct of 3-beta-benzoyloxybisnor5,7,9 (11) -cholatrien-22-al, melting at 183-187 degrees centigrade. 2,4-dinitrophenylhydrazone, melting at 224-249 degrees centigrade.

(4) Dimethyl maleate adduct of 3-beta-acetoxybisnor-5,7,9 (11) -cholatrien-22-al, melting at 172-178 degrees centigrade. 2,4-dinitrophenylhydrazone, melting at 238-244 degrees centigrade.

(5) Dimethyl maleate adduct of 3-hydroxybisnor-5,7,9 (11) -cholatrien-22al, melting at 163-170 degrees centigrade. 2,4-dinitrophenylhydrazone, melting at 250-254 degrees centigrade.

In a manner similar to the above, the maleic anhydride adduct of 3-hydroxybisnor-5,7,9(11)- cholatrien-22-al is obtained from dehydroergosteryl maleic anhydride adduct; the maleic acid adduct of 3-hydroxybisnor-5,7,9(11) -cholatrien- 22-al is obtained from dehydroergosteryl maleic acid adduct; and 3-acyloxybisnor-5,7,9(11)- cholatrien-22-al maleic acid adducts are obtained from the maleic acid adduct of 3-acyloxydehydroergosterols.

PREPARATION 9.DIMETHYL MALEATE ADDUCT OF 3HYDROXYBISNOR-5,7,9 (11) -OHOLATRIEN-22-AL A solution of 2.69 grams (.005 mole) of the dimethyl ester of the maleic acid adduct of dehydroergosterol, in eighty milliliters of methylene chloride, cooled by a Dry-Ice and trichloroethylene bath, was treated with ozonized oxygen until 247.36 milligrams (.0051 mole) of ozone was absorbed. The solution was then allowed to warm to room temperature, whereafter thirty milliliters of acetic acid was added and the methylene chloride removed in vacuo. While cooling in a waterbath at fifteen degrees centigrade, four grams of zinc dust was added in portions with stirring, the temperature being maintained between fifteen and twenty degrees centigrade. Stirring was continued for another fifteen minutes, whereafter the zinc was separated by filtration. The filtrate was diluted with water to cloudiness, extracted with ether, the ether extract washed with sodium bicarbonate and then with water to neutrality, the solution then dried over sodium sulfate and evaporated to dryness in vacuo. The residue was crystallized from acetic acid and water, giving 1.92 grams (81.5 percent of the theoretical) melting point 91-97 degrees centigrade, which yielded a dinitrophenylhydrazone derivative in 72.5 percent yield, melting point 212-238 degrees centigrade. The aldehyde was recrystallized and found to have a purified melting point of 163-170 degrees centigrade, while the dinitrophenylhydrazone derivative was recrystallized until a melt- A mixture of twenty grams of the maleic anhydride adduct of 3 -beta acetoxybisnor- 5,7,9(11) -cholatrien-'-22-al, six grams of anhydrous sodium acetate, and 600-milliliters of acetic anhydride, was heatedunder reflux for six hours, whereafter volatile components were removed under reduced pressure. The resulting solid was digestedwith five fifty-milliliter portions of boiling acetone for five minutes each, and the extracts combined and, diluted with 130 milliliters of water. There was thus obtained sixteen grams of the maleic anhydride adduct of 3-beta-acetoxy- 22acetoxybisnor-5,7,9 (11) 20 (22) -cholatetraene, which melted. at 186 to 193 degrees centigrade. Recrystallization of the crude" product from a mixture of acetone and pentane raised the melting point to 200.5 to 202 degrees centigrade.

prepared:

(1) The dimethyl maleate adduct of 3-betabenzoyloxy 22 acetoxybisnor-5,7,9(11),20(22) cholatetraene, which meltedat 210 to 211 degrees centigrade.

(2) The dimethyl maleate adduct of 3-betaacetoxy 22 acetoxybisnor 5,7,9(11),20(22) cholatetraene, which melted at 181to 183 degrees centigrade.

In the same manner as given above, 22-acyloxy, e. g., formoxy, vacetoxy, propionoxy, butyroxy, valeroxy, hexanoyloxy, heptanoyloxy, octanoyloxy, benzoyloxy,naphthoyloxy, and the like 3- acyloxybisnor-5,7,9 (11) ,20 (22) -cholatetraene adducts, are obtained from the compounds of Preparations 6, -'7, and-8. Such representative compounds include -3 formoxy-22-acetoxy-bisnor-5.- 7,9(11),20(-22) cholatetraene, 3-propionoxy-22- acetoxybisnor-5,7,9 (11) ,20 (22) -cholatetraene, 3,- 22 dlDl'OPlOIlOXYbiSIIOY-r5;7,9, (11) ,20 (22) cholatetraene,3;22-dibenzoyloxyebisnor-5,7,9, (11) 20 (22) -cholatetraene, and 3-heptanoyloxy-22-octanoyloxybisnor- 5,7,9(11),20(22) cholatetraene adducts withmaleic anhydride or maleic acid esters -such as the dimethylmaleate, diethyl maleate, dipropyl ma1eate,..diisopropyl maleate, dibutyl maleate, dioctyl maleate, dibenzyl maleate, and the like.

PREPARATION 12.lIALEIc ANHYDRIDE ADDUCT or 3-HETA-ACETOXY-5,7 ,9 (11) mnecxnramn-QO-oxe A solution of- 5.08 grams of the maleic anhydride adduct of 3beta-acetoxybisnor-5,7,9(11)- cholatrien-22-al enol-acetate in 100 milliliters of methylene chloride was-cooled to about minus seventy degrees centigradeand ozonized until 483 milligrams of ozone -had been absorbed. Fifty milliliters of glacial acetic acid was then added and the methylene chloride removed under reduced pressure. An additional thirty milliliters of glacial acetic acid was then added and the ozonide decomposed by adding seven grams of powdered zincat a substantially uniform rate while maintaining the reaction temperature between seventeen and-twenty degrees centigrade. The mixture was stirred for an additional twenty minutes, filtered, and the zinc washed with 140 milliliters of glacial acetic acid. The organic 12 extracts were combined and dilutedwith seventy milliliters of water. When crystallization comunenced, the rate of precipitation'was' increased by addition of two volumes of water. There was thus obtained 4.0 grams of the maleic anhydride adduct of 3-beta-acetoxy-5,7,9(11) -pregnatrien- 20-one, which melted at 240 to 264.5 degrees centigrade. Several recrystallizations of the crude material from acetone raised the melting point to 263.5 to 254.5 degrees centigrade.

PREPARATION l3.i\.l'ALEIC 'Acro AIJDUCT or 3421;11- HYDRoxr-5,7,9 11) -PREGN.-\TRIEN-20-ONE A solution of4.52 grams (0.0100 mole) of the maleic anhydride adduct of 3-beta-acetoxy- '5',7,9(1 -pregnatrien-20-one, M. P. 263-2645 degrees centigradeyina mixture of 100 milliliters of 1,4-dioxane and 400 milliliters of water containing four grams (0.10 mole) of-sodium hydroxide wasv allowed to stand at room temperature for two and-one-half hours, whereupon a small quantity of plate-like crystals formed. These were dissolved by heating the mixture to seventy degrees'centigrade for one-half hour.

The reaction mixture was then made acid with fifty milliliters of three normal hydrochloric acid and refrigerated to give. a precipitate of 3.05 grams of needle-like crystals-melting at 173-177 degrees centigrade. On crystallization from a dioxane-water:mixture; the compound melted at 211 215 degrees centigrade. The melting'point was found to vary somewhat with the rate of heating.

Analysis:

Calculated fOrCzsHszOs C,'70.07; H, 7.53 Found 'C, 69.80; H, 7.47

' PREPARATION 1-l.-'-DIMETHYL RIALEATE or 3-DETA- 1' Rumm -5,7,9 (11) LPREGNAIRIEN-QUONE A suspension of 0.400 gram of the maleate acid adduct of 3-beta-hydroxy-5,'7,9( l1) -pregnatrien- 20-one, in fifty milliliters of dry ether, was cooled in an ice-salt bath while a slight excess of diazomethane in methylene chloride was added over a 25 minute period with stirring. Ten minutes after addition was complete, the solution was placed on a steam bath and concentrated rapidly to dryness. The residue was crystallized from an acetone-water mixture to give 0.34 gram of the PREPARATION 15. 'DIMETHYL MALEATE or 3-BETA- AonroxY-5,7,9(11) -PREGNATRIEN-20ONE A solution of 0.15 gram of the dimethyl maleate adduct of 3-beta-hydroxy-5,7,9 (11) -pregnatrien- 20-one, in 2.5 milliliters of acetic anhydride and 2.5 milliliters of pyridine, was heated on the steam bath for ninety minutes-cooled toroom temperature, and poured into ice-water. The resultmg precipitate was collected by filtration and found to melt at 205-209 degrees centigrade. Recrystallization from methanol gave the dimethyl 13 maleate of 3-beta-acetoxy-5,7,9(l1) -pregnatrien- 20-one, melting at 207-211 degrees centigrade.

Analysis:

Calculated for (3291-1330": C, 69.86; H, 7.68 Found C, 69 81; H, 7.86

PREPARATION 16.MALEI ANHYDMDE ADDUCT 0F 3- BmA-HEPTAN OYLOXY-5,7 ,9 (11 -PREGNATRIEN-20-ONE The maleic anhydride adduct of 3-beta-heptanoyloxy-5,7,9 (11) -pregnatrien-20-one, melting point 170-171 degrees centigrade. was prepared by refluxing the maleic acid adduct of 3-beta-hydroxy-5 .7,9(11)-pregnatrien-20-one with heptylic anhydride and pyridine for a period of twenty hours, and working up the reaction prodnot in the usual manner.

PREPARATION 17.-MALEIc ANHYDRIDE ADDUCT or 3-BErA-HYDROXY5,7,9 (11) -PREGNATRIEN--ONE Similarly, the maleic anhydride adduct of 3- beta hydroxy-5,7,9('11)-pregnatrien 20-one, melting point about 195 degrees centigrade, was prepared by refluxing the maleic acid adduct of 3-beta-hydroxy-5,7,9(11) pregnatrien-20 one with Dowtherm for eight hours. The 3-hydroxymaleic anhydride adduct is also obtained by heating the 3-hydroxy maleic acid adduct to just above its melting point, which procedure causes water to be evolved, with the closing of the anhydride ring.

In the same manner as given above, still other 5,7,9(11) -pregnatrien-20-one adducts are prepared from the corresponding 3,22-diacyloxybisnor-5,7,9 (11) ,20 (22) -cholatetraene maleic acid, maleic acid anhydride, and maleic acid diester adducts. Such compounds include the 3- formoxy-5,7,9(11) pregnatrien-20-one maleic acid, maleic acid anhydride, dimethyl maleate, diethyl maleate, dibutyl maleate, dioctyl maleate, diisopropyl maleate, dibenzyl maleate, and like adducts; the corresponding S-propionoxy, butyroxy, valeroxy, hexanoyloxy, heptanoyloxy, octanoyloxy, naphthoyloxy, benzoyloxy, and similar 20-ketone adducts, including, for example, 3- propionoxy-5,7,9(11) -pregnatrien 20 one dipropyl maleate, 3-benzoyloxy-5,7,9(11)-pregnatrien-ZO-one dibenzoyl maleate, B-heptanoyloxy- 5,7,9(11)-pregnatrien-20-one dimethyl maleate, 3-valeroyloxy 5,7,9(11) pregnatrien-20 one maleic acid anhydride adducts, and the like.

PREPARATION 1.8.MALEI0 ANHYDRIDE Annuc'r on 3- BETA-,21-DIACETOXY-5,7 ,9 (11) -PREGNATRIEN-20-ONE The maleic anhydride adduct of 3-betaacetoxy 5,7,9(1l) pregnatrien-20-one (0.45 gram, .00'1 mole) and 1.33 grams of lead tetraacetate were added to milliliters of 98.3 percent acetic acid which had been distilled over chromium trioxide. The mixture was heated in a water bath maintained at about 56 degrees centigrade and allowed to stand at that temperature for seventy-two hours. The lead tetraacetate dissolved slowly during the first hour and went into solution. The solution was then evaporated in vacuo until only a few milliliters of solvent remained, the residue was dissolved in ether, washed with water, dried, and evaporated to dryness. Crystallization of the residue from alcohol gave 0.17 gram of maleic anhydride adduct of 3-beta-,21-diacetoxy-5,7,9(11) -pregnatrien-20-one, melting at 225 to 235 degrees centigrade. After several recrystallizations from methanol, the material melted at 240-243 degrees centigrade.

Analysis:

Calculated fOlCzcI-IsrOs--- C, 68.22; H, 6.71 Found C, 68.28; H, 6.75 68.15; 6.75

PREPARATION 19.DIMETHYL MALEATE ADDUCT OF 3- BETA-,21DIACETOXY5,7,9 11 -PREGNATRIEN-2Q-ONE In the manner of the preceding preparation, the dimethyl maleate adduct of B-beta-acetoxy- 5,7,9('11)pregnatrien-20-one was converted to the climethyl maleate adduct of 3-beta-,21- diacetoxy-5,7,9(11) pregnatrien-ZO-one, which melted at 210-214 degress centigrade.

Analysis:

Calculated for 0311-14009" C, 66.89; H, 7.14 Found C, 66.72; B3, 7.24 67.09; 7.34

In the same manner as given above, other 3- acyloxy, 21-acetoxy-5,7,9(11) pregnatrien-20 one adduots, including 3-formoxy, 2l-acetoxy- 5,7,9(11)-pregnatrien-20-one maleic anhydride adduct, 3-propionoxy, 21-acetoxy-5,7,9(11) -pregnatrien-ZO-one maleic acid adduct, 3-butyroxy, 21-acetoxy-5,7,9(11) pregnatrien-20-one dimethyl maleate adduct, 3-octanoyloxy,2l-acetoxy- 5,7,9(11) -pregnatrien-20-one dioctyl maleate adduct, 3-benzoyloxy,21-acetoxy-5,7,9 (11) -pregnatrien-20-one maleic anhydride, 3-heptanoyloxy, 21-acetoxy-5,7,9(11) -pregnatrien-20-one maleic acid adduct, and the like, are prepared from the corresponding starting compound which is unsubstituted in the 21 position.

Example 1Maleic anhydride adduct 0 3-beta-,

ZI-diacetoxy-QJl-oxido 5,7 pregnadien-ZO- one To a solution of one gram of 3-beta-,21- d1acetoxy-5,7,9(11) -pregnatrien-20-one in 25 milliliters of acetic acid was added a mixture of 1.5 milliliters of thirty percent hydrogen peroxide and six milliliters of acetic acid. The mixture was heated on the steam bath for four hours, cooled, and poured into 200 milliliters of ice water. The resulting solid was collected and dried. The yield was 0.91 gram, melting at -130 degrees centigrade. After several recrystallizations from acetone-skelly solve B (hexane), the compound, 3-beta-,21 diacetoxy-9,l1 oxido-5,7- pregnadien-ZO-one maleic anhydride adduct. melted at 125 degrees centigrade, resolidified at about -140 degrees centigrade, and remelted at 223-228 degrees centigrade.

Example 2.--Dimethyl maleate adduct 0 3, 21- dzacetory-ll: 11-omz'do-5, 7-pregnadz'en-20-one To a solution of 0.5 gram of maleic anhydride adduct of 3,21-diacetoxy-9:ll-oxido5,7-pregnad1en-20-one in thirty milliliters of methylene chloride and forty milliliters of methanol cooled in an ice bath, was added fifty milliliters of diazomethane-methylene chloride solution in two twenty-five milliliter portions ten minutes apart. The mixture was allowed to stand in the ice bath for two hours and thereafter at room tem-- perature for thirty minutes. It was then concentrated on the steam bath to fifteen milliliters.

' 186-190 degrees centigrade.

J Example grade for one hour. is followed by removing aliquots at different time and water addeduntilcrystallization took place. 'Aftercoolingahd filtering there was obtained 0.41 gram of 3,2l-diacetoxy-9:ll'-oxido-5,7-pregnadien-20-one. dimethyl' maleate adduct, 'M. P.

The same compound is produced by epoxidation of 3,21-diacetoxy-5,7,9 (11)-pregnatrien -20-one dimethyl maleate adduct according to the manner of Example 1, using hydrogen peroxide in a glacial acetic acid medium.

3.-3'-acetoxy-21-hydrowy-9,11-oxido- 5,7-pregnaaien-20-one maleic acid adduct ond solution consisting of 0.5 normal sodium hydroxide solution and 350 milliliters of water is'cooled in an ice bath and then added to the dioxane solution. The volume of the mixture is then brought to 500 milliliters by addition of water and allowed to stand at zero degrees centi- The speed of saponification intervals and titrating with standard hydrochloric acid. At one hour, three equivalents of base are used up, the reaction mixture is made acid to Congored paper with ten percent hydrochloric acid and concentrated on the steam bath in vacuo to about one hundred milliliters. This causes crystallization of 3-acetoxy-21- hydroxy- 9,11-oxido-5,7-pregnadien-20-one maleic acid adduct. The same product is obtained by hydrogen peroxide epoxidation of the 9,11-double bond of 3-acetoxy-21-hydroxy-5,7,9(11) pregnatrien- 20-onemaleic acid adduct, M. P. 235-240'degrees centigrade, prepared'by' saponification of 3,21- diacetoxy 5,7,9(11) -pregnatrien -"2O one maleic anhydride adduct.

Example 4.3 -aceto:cy 21 hydroacy 9,11-

- oxido-5,7-pregnadien-20-one maleic. anhydride adduct Without further purification, the acid thus produced in the preceding example is placed in a vacuum oven and heated for'tenhours at 136-140 degrees centigrade at eight to ten millimeters Example 5.-3,21-dihydroa:y-9,1I-oxido-SJ-pregnadien-ZO-one maleic acid-and'anhydride adducts If in the above procedure of Example 3 the saponification is allowed to proceed further, until four equivalents of base are used, both the 3 g and 21 acetoxy groups are removed and the 3,21-

dihydroxy 9,11 oxido 5,7 pregnadien 20- one maleic acid is produced, which can then be converted to the anhydrideby heating in a vacuum according to the manner of the preceding example. These products are also prepared by hydrogenperoxide epoxidation-of the 9,11-double bond of 3,21-dihydroxy-5 ,7,9(11)'-pregnatrien- ZO-one maleic acid or anhydride adducts, which are prepared in a manneridentical tothat given above for the oxido compounds, by saponification of 3,21 diacetoxy 5,7,9(1l)-pregnatrien-20- one maleic anhydride with four equivalents of base, and heating the resulting dihydroxy diacid in a vacuum, respectively.

Other adducts of 3-acyloxy-9,11-oxido-5,7 pregnadien-20-one-2l-acetates include 3-valeroyloxy 9,11 oxido 5,7 pregnadien 20- one-21-acetate maleic acid adduct, 3-heptanoyloxy 9,11 oxido 5,7 pregnadien 20 one- 2l-acetate maleic anhydride adduct, 3-benzoyloxy 9,11 oxido 5,7 pregnadien 20 one- Zl-acetate dimethyl maleate adduct, 3-formoxy- 9,11 oxido 5,7 pregnadien 20 one 21- acetate maleic anhydride adduct, 3-acetoxy-9, 11 oxido 5,7 pregnadien 2O one 21 acetate maleic acid adduct, 3 propionoxy 9,11- oxido5,7-pregnadien-20-one-2l-acetate dirnethyl maleate adduct, 3-butyroxy-9,11-oxido-5,7-pregnadien-ZO-one-Zl-acetate diethyl maleate adduct, 3 octanoyloxy 9,11 oxido 5,7 pregnadien-ZO-one-Zlacetate dioctyl maleate adduct, 3 benxoyloxy 9,11 oxido 5,7 pregnadien-20-one-2l-acetate maleic anhydride adduct, 3 propionoxy 9,11 oxido 5,7 pregnadien-20-one-2l-acetate maleic anhydride adduct, and the like, which are prepared in the same manner from the selected starting compound.

In the same manner as given for the preparation of 3-acyloXy-9,11-oxido-5,7-pregnadien-20- one-21-acetate maleic anhydride adducts, the corresponding maleimide and N -alkyl maleimide 'adducts are prepared from the corresponding apparent to one skilled in the art, and the invention is therefore to be limited only by the scope of the appended claims.

We claim: 1. A 9,1l-oxido-5,7-pregnadien-20-one adduct represented by the formula:

wherein X is selected from the group consisting of hydrogen and acetyl, wherein R is selected from the group consisting of hydroxy and PJCOO-R being selected from hydrogen and a hydrocarbon radical containing from one to "seven carbon atoms, inclusive, and wherein A is an adduct radical of a dienophile of the group consisting of maleic acid, maleic anhydride, and di-lower-alkyl esters of maleic acid, wherein the esterifying groups are of solely hydrocarbon nature and contain from one to eight carbon atoms, inclusive.

' 2; A 3-acyloxy-9,11-oxido5,7-pregnadien-20- -one-21-acetate maleic anhydride adduct, wherein th acyloxy group is of the formula RCOO,

R being selected from hydrogen and a hydrocarbon radical containing from one to seven carbon atoms, inclusive.

3. 3 acetoxy 9,11 oxido 5,7 pregnadien- 20-one-21-acetate maleic anhydride adduct.

4. 3,21 dihydroxy 9,11 oxido 5,7 preg- 5 nadien-20-one maleic acid adduct.

5. 3 acetoxy 9,11 oxido 5,7 pregnadien- 20-one-21-o1 maleic acid adduct.

6. 3,21 dihydroxy 9,11 oxido 5,7 pregnadien-20-one maleic anhydride adduct.

7. 3 -acetoxy 9,11 oxido 5,7 pregnadien- 20-one-21-o1 maleic anhydride adduct.

ROBERT H. LEVIN. A VERN MCINTOSH, JR. GEORGE B. SPEED.

18 REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,265,143 Butenandt Dec. 9, 1941 2,312,344 Logemann Mar. 2, 1943 

1. A 9,11-OXIDO-5,7-PREGNADIEN-20-ONE ADDUCT REPRESENTED BY THE FORMULA: 